Increasing data rates and higher Quality-of-Service (QoS) offered by current and developing wireless communication networks provide the users of such networks with new opportunities to consume a variety of electronic content via their various types of wireless devices. It is now commonplace for users to watch movies, videos, and/or browse media-rich web content via their smartphones, tablets, and other media consumption devices. Here, the term “media consumption device” broadly denotes essentially any type of wireless device or apparatus that has a wireless communication network interface, e.g., a cellular network transceiver and associated authentication and protocol processing, and further has one or more audio and/or video interfaces, to allow for content consumption by a user of the device.
Content caching represents a known technique for managing content consumption within communication networks and within the one or more packet data networks—e.g., the Internet—that originate the various items of content being consumed by users within the wireless communication network. With content caching, the network operator or other entity caches at least some content, e.g., content that is known or expected to be popular with users of the wireless communication network, in a network cache that generally resides in or operates in conjunction with a Core Network (CN) portion of the wireless communication network.
For a number of key reasons, this type of network caching conventionally operates at the packet data network interface of the wireless communication network. Performing caching at the packet data network interface—i.e., at point where CN packet gateway provides incoming and outgoing routing of user-plane Internet Protocol (IP) traffic—the network operator maintains full visibility of caching operations for billing and lawful intercept purposes.
For example, in the context of a 3GPP network based on the GSM (Global System for Mobile communications) or the WCDMA (Wideband Code Division Multiple Access) standard, caching may be implemented at the GGSN level, where “GGSN” denotes Gateway GPRS Support Node, and “GPRS” denotes General Packet Radio Services. The GGSN is a CN node that operates as the IP anchor point for wireless devices operating within the RAN. As such, the GGSN maintains the routing information necessary to tunnel protocol data units (PDUs) for specific wireless devices to the Serving GSNs associated with the particular areas of the RAN in which respective ones of those wireless devices are operating. In turn, the RAN includes radio nodes, such as “NodeBs” in the WCDMA context, each of which provides radio coverage over one or more given cells or other such service areas.
Broadly, the GGSN performs IP address assignments for wireless devices connected to the wireless communication network and operates as the default router for connected wireless devices, which are referred to as “User Equipments” or UEs in the 3GPP context. User-plane traffic, including content requests, such as HTTP Get requests, originate from given wireless devices and flow through GTP tunnels from the RAN to the SGSNs/GGSN. Here, “GTP” connotes the GPRS Tunneling Protocol. A network-level cache operates at the GGSN level, e.g., by providing cached content that would otherwise be sourced from a packet data network external to the wireless communication network.
While such network-level caching offers certain efficiencies as compared to a scenario where requested content is always sourced from the targeted content origin servers, it is recognized herein that significant disadvantages attend conventional network-level caching. For example, even though cached content does not have to be sourced from outside of the wireless communication network, the wireless communication network is obligated to “back haul” cached content from the CN to the radio nodes in the RAN that serve the wireless device(s) that requested the cached content. Here, the term “back haul” denotes the transport of traffic and/or signaling over the communication links between the CN and the RAN, and it is recognized herein that bandwidth on back-haul communication links remains a relatively constrained resource, even in contemporary and developing networks.
Correspondingly, it is further recognized that back-haul link congestion affects the quality of experience for users that are consuming content. For example, back-haul link congestion can result in the need to serve lower-quality streams, e.g., by serving video and/or audio content at higher compression levels and at reduced bit rates. Such congestion also can result in dropped connections, latency, jitter, and other pathologies that degrade the users' content consumption experience.
These problems become particularly acute for certain high-bandwidth services, referred to as broadband content and exemplified by High Definition (HD) movie streaming. Acute problems also arise for certain consumption phenomena, such as the “flash crowd” phenomena, which places severe burdens on the back haul and is characterized by a potentially large number of users within the same location (e.g., a football stadium) requesting content at the same time or at overlapping times.
While such problems are presented in the context of GSM and/or WCDMA networks, with or without High Speed Packet Access (HSPA) services, they are equally applicable to a variety of other wireless communication networks. For example, in a Long Term Evolution (LTE) context, the wireless communication network is implemented according to the System Architecture Evolution or SAE, wherein the CN is an Evolved Packet Core or EPC. In turn, the EPC includes an SAE gateway that provides the same or similar functionality as the above-described GGSN, and works in conjunction with a Mobility Management Entity (MME) that provides mobility management for wireless devices operating within the RAN portion of the wireless communication network. Further in the LTE context, the RAN includes radio nodes that are referred to as eNBs, and which connect via an S1 interface to the EPC.